Cosmic reionization is a period in the Universe history when it switched from being predominantly neutral to mostly ionized. We still haven’t quite pinned down the source(s) that caused this transition, but we have our suspicions. It could be quasars. It could be galaxies. Or could it be something else?
[Figure from universe-review.ca/F05-galaxy06.htm]
By measuring the black hole mass and velocity dispersion of currently merging galaxies each in various stages of a merger, the authors conclude that the growth of the central super massive black hole occurs in the early stages of each merger and outpaces any bursts of star formation or central bulge growth.
When two observations share some common information, they can be “cross-correlated” to extract it. In today’s example, we discover what the matter halos and energetic phenomena in the Universe have in common through a cross-correlation.
Direct observational evidence for positive feedback from the interaction of outbursts from active black holes and the surrounding medium has been lacking so far, until now…
The diffuse gas contained within galaxy clusters can dramatically affect the galaxies moving within it. This includes bending the jets coming out of active galactic nuclei in galaxy clusters. The authors in today’s Astrobite report on extremely bent jets recently discovered in galaxy NGC 1272.
Mergers make bulges in galaxies and black holes generally live in bulges, so mergers must grow black holes – simple. That was until we found bulgeless galaxies containing growing black holes…